ACL Reconstruction with the LARS Ligament
Anterior cruciate ligament is one of the four major ligaments of the knee that connects the femur (thigh bone) to the tibia (shin bone) and helps stabilize the knee joint. Anterior cruciate ligament (ACL) injury is one of the common injuries of the knee. An injury to ACL most commonly occurs during sports or activities that involve twisting, overextending, landing from a jump incorrectly, and abrupt change in direction or speed of movements.
When you injure your ACL, you might hear a "popping" sound or feel as though the knee has given out. You might experience swelling, pain, and gait disturbances. If left untreated, a torn ACL may lead to instability and recurrent giving way of the knee.
With recent advances in technology, it is now possible to repair the torn ACL with the utilization of an artificial Ligament Augmentation Reinforcement System (LARS), that is biocompatible with the native tissues of the body, rather than the traditional method of using a hamstring or patella tendon. LARS acts as a supporting band within the knee to promote healing of the ruptured ACL. It can either be implanted alone or in combination with suturing to the remnant of the injured ligament for reconstruction. LARS is usually indicated in acute injuries, in people with a good ACL stump that has a rich blood supply.
The LARS is composed of polyethylene terephthalate – an industrial-strength polyester fibre. The LARS ACL encompasses a pattern of intra-articular fibres arranged in either clock-wise or anti-clockwise direction to imitate the original ligaments within the knee. The structure of the LARS permits for new tissue ingrowth whereas the ruptured ligament remnants grow into the graft to increase the strength and stability of the ligament.
Surgical technique:
The goal of ACL reconstruction surgery is to stabilise your knee and to restore its stability.
This procedure uses minimally invasive technique; a smaller incision is placed than the traditional larger open incision. LARS is associated with minimal complications since an artificial ligament is used rather a native tissue graft.
An arthroscopic technique is employed to place the new ligament in situ. Tiny holes will be drilled through the remnants of the original ACL. The ligament is fitted into the bony holes and is enclosed by the native tissue. Additional fixation is done using a metal screw and a pin to hold it into place while the ligament heals into the bone.
Some of the potential benefits of using a LARS ligament in the repair of a torn ACL include:
- Minimal trauma to the surrounding structures
- Shorter recovery time and faster return to sport
- less post-operative pain
- Decreased muscle atrophy
Potential problems with the LARS ligament are:
- A higher risk of failure of the graft compared to traditional techniques
- Revision surgery is more difficult due to the need to remove the synthetic ligament.
I offer LARS ACL reconstruction selectively to patients who have a short term need for rapid return to full physical activity, and who accept that the failure rate of LARS ACL reconstructions is higher than for traditional hamstring or patella tendon techniques.